Now you have to edit the configuration files:
sudo gedit /lib/udev/rules.d/95-keyboard-force-release.rules

Note: in the samsung section you will see a line with *N130*|*N140* etc. add your model number there (don’t forget to Save). For example mine is N148 plus but I added |*N148*| and it works.

Also run:
sudo gedit /lib/udev/rules.d/95-keymap.rules

Add your model number if it isn’t already there (don’t forget to Save).

Finally, restart your computer.

The first part loads the samsung tools and backlight utility. This will also get some of your other function keys working. You can see the mappings in System>Samsung Tools Preferences.
The second part gets the mappings working for the Fn-up and Fn-down keys. it also keeps the Fn-keys from going crazy by forcing them to release after being pressed.